Water cooling, also known as liquid cooling, is a method for cooling hot components in your PC. It is the ideal solution for removing heat quickly and silently. Unlike stock coolers that use air flow and create noise, the water-cooling systems use water which has much better heat transferring abilities.

Water cooling systems are much more efficient in heat removal and offer a much better experience whether using your PC for work or gaming.
The water-cooling reservoir holds the extra liquid in a loop to allow for air bubbles to slowly be replaced by liquid as it circulates. The reservoir also serves as the filling port for liquid coolant. It can be installed as a standalone unit or as part of a pump/reservoir combo. It is essential to design your loop so that the reservoir is always before the pump.

There are two types of water cooling: combo and separate. In this article, you will find information with regards to both. You will read everything you need to know to identify the best water-cooling system for your requirements. You will also find the pros and cons of your best pump reservoir combo options.

The Best Water Cooling Reservoirs

XSPC Photon Tube ReservoirCheck Price
EKWB EK-RES X3 250 RGB ReservoirCheck Price
Koolance BDY-TK240X70 Reservoir Body Check Price

XSPC Photon Tube Reservoir

XSPC Photon Tube Reservoir is a great tube reservoir for cooling your PC. The tube is crafted by high-quality glass which is extremely durable. In the center of the tube, there is an acrylic 5mm LED lighting pole attached to the base of the reservoir. LED can easily get replaced to match the color scheme of your choice. Unlike other reservoirs that use cheap plastic, XSPC Photon features a high-quality aluminum bracket. The bracket is connected at both ends of the reservoir offering a clear view of the tube. Each reservoir is handcrafted and is tested under pressure to ensure reliability.
It has 3x G1/4″ Ports and its dimensions are: 270 x 75 x 75mm.

Pros Cons
LED easy to replace
Color matching scheme
Aluminum bracket
Silent, no leaks, good water flow
Difficult to adjust the fan speed
Big size – check the dimensions before purchase

EKWB EK-RES X3 250 RGB Reservoir

The EK-RES X3 250 RGB is a versatile multiport reservoir. It has a pre-installed 4-pin 12V RGB LED stripe that is compatible with every major motherboard manufacturer and mainstream RGB controller. Also, it is a cylindrical standalone option, manufactured from premium quality 60mm acrylic tube. It features POM Acetal end caps in black color. An airtight sealing is ensured by quality EPDM rubber washers at both ends of the reservoir. It has six G1/4″ ports, which make filling the tube routing and draining, an easy job.

Building a loop with this reservoir is quite simple due to:

  1. the number inlet/outlet port configuration options
  2. the simple and effective mounting kit

The characteristics of this reservoir are: Installation height: 250mm – Diameter: 60mm – Capacity: ~440ml

It is advisable to take care when cleaning the acrylic reservoir. Alcohol derivatives or other solvents might cause cracks.

Please note the following instructions from the manufacturer:

  1. With ports #3, #4 or #6 it is required to use the enclosed EK-Extender G1/4″ due to the ports being recessed into the plastic Reservoir Bottom.
  2. Be patient with EK-Extender G1/4 make sure not to use fittings or barbs with G1/4″ thread longer than 5mm!
  3. With ports, #1 and #2 make sure not to use fittings or barbs with a diameter larger than 25mm!
  4. Port #6 of EK-RES X3 series reservoir should only be used to connect this reservoir with an external fill port.
Pros Cons
Numerous ports
Easy to build the loop
You need to be careful with threads and fittings
Non-standard connectors at the bottom

Koolance BDY – TK 240X70 Reservoir Body

Koolance offers reservoir bodies for the expansion or replacement of your current reservoir. Each acrylic tube can be easily adapted to satisfy all water-cooling needs. You can mount it and use it both horizontally or vertically.

The inside of the tube is equipped with a fin to eliminate vortexing in the reservoir. You have two options for the installation of fittings: At the side or the lower end. The vacant connection threads can be sealed with the included screw plugs.

The optional top and bottom expansion are made from sturdy Acetal. The top piece is also equipped with an opening which is especially interesting for the integration of fillports. You can disassemble the whole reservoir for easy cleaning.

All connection threads on the expansion pieces are 1/4″ threads for maximum compatibility. With an expansion piece, two tubes can get connected.

The specifications are: Length: 240mm – Diameter: 80mm – Capacity: 924ml

You can use the Koolance BDY-TK240x70 reservoir Body drawing to help in deciding the reservoir to best suit your water cooling reservoir needs.

Pros Cons
Available for expansion or replacement of the reservoir
Acrylic tube, capacity: approx. 924ml
Can be mounted horizontally or vertically
Can be mounted horizontally or vertically
The guarantee is valid only if operated with distilled water or with water additives and/or finished mixtures of specific manufacturers
You need to be careful with installation and fittings

Pump Reservoir Combo

You can either buy the components separately, or you can buy the Pump/Reservoir Combo. It comes down to your personal preference and an assessment of your individual needs.

The Reservoir – Pump Combo is a straightforward and safe option. The coolant and the pump will work together without any problems. In the market, you can find several Combo options incorporating the cylindrical reservoir. There is also the option of the ‘Bay’ Pump Reservoir Combo, which we are not going to discuss as it is gradually becoming redundant.
With the classic cylindrical reservoirs, the reservoir is placed on top of the pump, so that coolant is always available. In case the pump functions on dry it could get ruined. Check for the size that fits your requirements and makes sure the combo unit has the proper mounting equipment.

A Pump Reservoir Combo Unit usually shares the same mounting apparatus. Regarding separate solutions, both the pump and reservoir need their separate installation equipment.

As far as reservoirs are concerned – both standalone or combo – it is best that you chose a model that has an anti-cyclone solution.

The anti-cyclone insert is important so that you don’t get the “tornado” effect in the reservoir, which can result in air being sucked through the loop and creating problems in the water blocks and radiators. Also, you can find our related article about the best water cooling pumps if you decided to install water cooling separately.
Performance is not determined by the use of either a combo or separates. The main criteria would have to be

  1. What works best for your PC;
  2. The visual outcome of your desire.

Thermaltake Pacific DIY LCS PR 22 D5 Reservoir – Pump Combo

The Thermaltake Pacific PR Series tube reservoir and D5 pump enable you to customize your PC water cooling configurations. This combo offers both reliability and outstanding performance. It is manufactured from high-quality POM and PMMA material to provide a crystal clear, high performance, robust solution.

As a result, it is an exceptional choice for PC users offering supreme mounting, fitting and flow.  It comes with two capacity options: 200ml or 300ml.

The main features of the Thermaltake Pacific DIY LCS PR 22 D5 Reservoir – Pump Combo is:

  1. Strong Performance. Made in Taiwan, the top cap supports rubber washers for a proper seal, including two predrilled G1/4” ports for fittings. Featuring 6mm thick of the pipe wall, it can sustain the maximum pressure up to 99 PSI. You can easily open out the top cap to clean the reservoir.
  2. Heat-resistant Acrylic Tank. The Pacific PR Series tube reservoirs are all made of reliable, light POM and PMMA construction – crystal clear and highly durable. The tube is made from high-quality acrylic with a maximum working temperature: 131℉(55℃).
  3. Easy and Flexible Application. Along with two brackets connected to both ends, Pacific PR Series is solid hold inside the chassis and allows you to build an exquisite cooling system with upgrade options. You can install it either horizontally or vertically.
  4. Ultimate Speed Controller and High-lift Pumping. This combo is designed with a manual speed control knob to provide five speeds. Maximum discharge up to 1135L/hr provides high-performance cooling to your components. High-lift pumping of the pump head reaches up to 15 feet high at the maximum speed.
  5. The pump is compatible with Thermaltake Pacific Series reservoirs and fittings, giving you the option to increase the performance of the system.
Pros Cons
Sustains the maximum pressure up to 99 PSI
The Manual speed control knob
Silent Kit pump cover
Capacity: 200ml or 300 ml
Easy installation
Maximum discharge is 1135 l/hr
Multiple mounting options
Maximum working temperature is lower compared to other pumps (55°C)
Coolant might fade over time
Certain caution measures are to be followed, such as:

  • using pre-mix coolant,
  • filling the reservoir from the top

XSPC D5 Photon Reservoir/Pump Combo V2

The XSPC D5 Photon Reservoir/Pump Combo combines the ultimate tube reservoir with the best pump available for PC water cooling.

The D5 Vario pump features superior performance and reliability. The speed dial allows you to adjust the speed according to the requirements of your system, and the tacho output lets you accurately monitor the pump’s speed.

The tube is made of high-quality glass which is exceptionally durable. In the center of the tube, there is an acrylic 5mm LED lighting pole attached to the base of the reservoir. LED can easily get replaced to match the color scheme of your choice. Unlike other reservoirs that use cheap plastic, XSPC Photon features a high-quality aluminum bracket. The bracket is connected at both ends of the reservoir offering a clear view of the tube. Each reservoir is handcrafted and is tested under pressure to confirm reliability.

V2 Photon reservoirs include a new bracket which attaches directly to 120mm and 140mm radiators. It also has an improved fill port with lower restriction, to make filling the reservoir easier. Photon reservoirs can be used either horizontally or vertically. If using the Photon horizontally, make sure to keep it topped up to the top so that air doesn’t get sucked into the loop.

Pros Cons
LED easy to replace
Color matching scheme
Aluminum bracket
Silent, no leaks, good water flow
Difficult to adjust the fan speed
Big size – check the dimensions before purchase
No vertical stand

EKWB EK-XRES 140 Revo D5 RGB PWM

EK-XRES 140 Revo D5 PWM is a high-performance water-cooling pump with an integrated reservoir. The core of the unit is the Xylem D5 PWM water pump.

The EK-XRES Revo D5 series comes with a rounded design that offers great usability and allows installation at any angle within 360° of rotation. The special rubber shock absorber is used to de-couple the main pump body from the mounting clip for silent operation, free of vibration noise. Horizontal and vertical positioning is supported to enable more tube routing options.

EK-XRES 140 Revo D5 series reservoirs come preinstalled with an anti-cyclone insert. This water pump/reservoir combo unit can be mounted directly on computer chassis using the enclosed Revo D5 Holder.

The tube is made of quality acrylic material, and the reservoir bottom/pump top is made of quality POM Acetal material. This reservoir can get upgraded with longer acrylic tubes used by EK-RES X3 series reservoirs.

A significant benefit of EK-XRES 140 water cooling pump is its compatibility with RGB sync technologies from all the major motherboard manufacturers.

If you are looking for an advanced and easy to use water cooling pump, this is the pump that will fulfil your requirements.

Pros Cons
Instructions are clear and easy to follow – come with all the tools and hardware needed
The pump offers increased hydraulic performance
Comes with 2 options for vibration dampening
Well polished with bright lighting
Can get easily disassembled for cleaning/flushing
Maximum liquid temperature is 60°C
Silent even at maximum flow
No leaks
The pump is water lubricant – it is advisable not to run it dry
The pump bracket is not included in the unit
The RGB power cable is not very long; buy an RGBW extension if your pump isn’t near your motherboard.
No independent drain port built into the pump

Nowadays PC users often need to cool their PC hardware to keep it functioning properly and avoid a crash. Several water-cooling options are now available, either as stand-alone pumps and reservoirs or as combo units. Both options have their advantages and disadvantages. In terms of performance, there is no black or white answer. It depends on your aesthetics and your personal preferences, both technical and visual. In this article, I presented in detail numerous water cooling options and offered you all the information you need to make the right decision. Feel free to send me your comments below and share your views and experiences.

Leave a Comment